JPS582818B2 - Manufacturing method of rock wool board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a rock wool board that is less susceptible to deflection due to moisture.

Traditionally, rock wool boards were used as ceiling materials, for example.
It has excellent heat insulation and sound absorption properties, and is highly praised for its performance, but it has a tendency to absorb moisture and sag, which poses a problem in practical use.

First, an example of the conventional manufacturing method for rock wool board is as follows: A water-based slurry made by mixing the main ingredient rock wool and a binder is made into a paper to obtain a water-containing mat, which is then subjected to pressure to give it the desired surface decoration, and then dried. The rock wool boards were completely dehydrated and manufactured into rock wool boards, but as mentioned above, the rock wool boards flexed significantly when they were put into use.For example, when ceiling materials were placed between roof porches, the center of gravity tended to shift downward. There was a phenomenon of depression.

Therefore, the deflection was reduced by applying thermosetting resin such as phenol resin or melamine resin to the back side of the rock wool board to form a watertight film, but this eliminated the disadvantages in terms of raw materials, process, and economics. It was something I was looking forward to doing.

The present invention has been made in view of the above facts, and provides a method for manufacturing a rock wool board with little deflection.

Therefore, the present invention is characterized in that it combines a shaping process of forming and drying a water-containing mat containing a rock wool plate and a fresh water-based binder, and a humidity conditioning process of impregnating the shaped plate obtained in the shaping process with water. That is.

The present invention will be explained in detail below.

First, the shaping process will be explained. For example, a water-containing mat is obtained by forming an aqueous slurry containing defibrated rock wool and a hydrophilic binder as main components, and adding reinforcing agents, fillers, and agglomerates as necessary.

Examples of hydrophilic binders used include starch, carboxymethylcellulose, polyvinyl alcohol, sodium alginate, and sodium polyacrylate.
Usually 2 to 15 parts by weight of rock wool (hereinafter referred to as parts)
It may be added in a proportion of 100%, and may be selected depending on the purpose and performance.

Note that the amount of the hydrophilic binder added is not limited.

In addition, water-containing mats are not limited to those produced by the so-called wet method in which paper is made from an aqueous slurry as described above. There is no particular limitation, and it may be done by a so-called dry method in which a necessary amount effective for binding is added and shaped.

This water-containing mat is then transferred to a pressurization and drying process.

Here, the density and wall thickness are adjusted to an appropriate level by pressurization, the moisture contained inside is physically dehydrated, and the moisture remaining inside is evaporated at high or low temperatures to create rigidity. Use it as a shape plate.

In addition, when applying a concavo-convex pattern to the surface, a suppression plate having concaves and convexes is used during pressurization in the shaping process.

The above method is commonly used as a conventional manufacturing method for rock wool boards, and the finished product is not ready for use at this stage.The features of the present invention are as follows.

That is, the present invention is characterized in that the shaped plate obtained in the above-mentioned shaping process is subjected to a humidity conditioning process in which it is impregnated with water.

Here, when the dehydrated and as anhydrous shaping plate is made to contain water by curing it under high humidity, the hydrophilic binder that functions to bind the solidified rock wool in the shaping process becomes slightly viscous and becomes active. be converted into

In other words, the activated hydrophilic binder releases the connective tissue of rock wool that was restrained by the forced pressure applied during the shaping process.
The forced restraint of the connective tissue is released and stabilized.

Therefore, when used for example, the connective tissue remains stabilized and no flexure occurs despite changes in humidity and temperature.

In addition, as a means of hydrating in this step, spraying or
Further, curing may be performed under high humidity or in the presence of heated steam.

The water content is 20 parts per 100 parts of the hydrophilic binder.
~400 parts is appropriate.

The reason for this is that if it exceeds 400 parts, it will swell and the bending strength will decrease, resulting in a loss of rigidity and if it is less than 20 parts, it will not be activated and the forced restraint of the connective tissue cannot be released.

Furthermore, if it is necessary to reduce the water content of the rock wool board impregnated with water as described above, it may be dehydrated and dried at atmospheric pressure or lower.

It is preferable to dry at 130°C or lower.

This is because dehydration and drying above normal pressure will forcefully restrict the connective tissue of rock wool.

Also, as a final step, the surface of the rock wool board is cut.

Alternatively, supplementing the surface treatment step of painting to enhance the surface performance may be carried out as required.

As described above, the present invention can correct the deflection caused by moisture by releasing the restraints of the rock wool connective tissue of the shaped plate.

Examples and comparative examples of the present invention are listed below.

Example 1 Rock MIOO part, starch 6 parts, wax emulsion 0 parts
．． 5. An aqueous slurry containing 0.01 part of polyacrylamide resin and having a rock wool concentration of 3.5% by weight was sifted through a 14-mesh wire mesh to obtain a water-containing mat.

This water-containing mat was pressurized at 2 kg/cm2 and further heated to 180°C.
After drying for 3 hours, a shaped plate with a thickness of 12 mm was obtained.

The moisture content of this shaped plate was measured to be 0.6% by weight (dry weight basis).

Note that the specific gravity was 0.37.

Furthermore, the cutting piece obtained by cutting a part of this shaped plate was heated to a relative humidity of 9.
0%, and was cured for 12 hours at a temperature of 30°C to control the humidity to obtain a rock wool board with a moisture content of 4% by weight.

A test piece was prepared from this rock wool plate, and compared with the one described in the comparative example, it showed extremely high physical properties in terms of Young's modulus and deflection in bending as shown below.

Bending Young's modulus: 260 kg/cm2 Deflection: 1.4 mm Example 2 The cut piece of the rock wool board obtained in Example 1 was further dehydrated by drying with hot air at 110° C. for 30 minutes.

The physical properties of this dehydrated rock wool board were extremely high compared to those described in Comparative Examples, as shown below.

Bending Young's modulus 250kg/cm2 deflection
The moisture content of this dehydrated rock wool board was 0.5% by weight, and the specific gravity was 0.37.

Comparative Example The physical properties of the shaped plate obtained in Example 1 were as follows.

Bending Young's modulus 100kg/cm2 deflection
17.3mm In addition, Example 1
, 2 and Comparative Examples were measured under the following conditions.

(1) Young's modulus in bending ■The product was left at a relative humidity of 90% and a temperature of 30°C for 8 hours, supported at a distance of 70 mm between two points, and a load was applied at a loading rate of 10 mm/min to measure the load and deflection. .

■ A test piece was cut into 40 mm x 70 mm with a thickness of 12 mm.

(2) Deflection■ 2-point interval 5 for 24 hours at 90% relative humidity and 30℃ temperature
The deflection when supported at 00 mm was measured.

■ A test piece was cut into 50 mm x 600 mm with a thickness of 12 mm.

Claims (1)

[Scope of Claims] 1. Combining a shaping process of pressurizing and drying a water-containing mat containing rock wool and a hydrophilic binder, and a humidity conditioning process of impregnating the shaped plate obtained in the shaping process with water. A manufacturing method for rock wool board featuring the following. 2. A method for producing a rock wool board according to claim 1, using starch as a hydrophilic binder.